Engineering and Design FAQs Advanced Topics Anchor Bolts and Base Rings Appendix 2 Flanges ASME B16.5/B16.47 Flanges ASME Code Addenda Bolted Covers Building Codes Cones (Transitions) Cylinders Deficiencies and Warnings Drafter External Loads External Pressure Finite Element Analysis (FEA) Flanges Forms Heads Heat Exchangers Hydrotest Impact testing Internal Pressure Joint Efficiency Legs Lifting Lugs/Clips/Stiffener Beams Materials MAWP/MAP MDMT Nozzles Pipe/Couplings/Pipe Caps Program Operations Radiography Reports Rings Saddles Support Skirts Thickness Calculations Transitions Units of Measurement Vacuum Rings Verification Welds WRC-107 Calculations Computer and Systems Administration (IT) FAQs Codeware Key Update Utility Error Messages Networking Program Troubleshooting Security/Hard Lock Key Issues (HASP) Software Updates/Installation Advanced Topics and U-2(g) Top Can ASME Section VIII Division 1 and COMPRESS be used at design pressures greater than 3000 psi? How does COMPRESS calculate the fundamental period of vibration (frequency) for vertical pressure vessels? I see there is a consideration for lethal service in the COMPRESS Design Settings Summary. Where is lethal service specified in COMPRESS? Does COMPRESS consider vortex shedding? How do I turn vortex shedding on in COMPRESS? How do I change the UG-22 loadings specified in the Settings Summary? Does COMPRESS consider the required thickness for longitudinal stress? What loads and vessel conditions are considered? How do I turn on consideration of tower/column deflections due to wind in COMPRESS? What is ASME Appendix 1-10? Why does COMPRESS apply Division 2 rules for nozzle design to my Division 1 vessel? Can the ASME Code be used for vessels that are to be installed in Europe? Does the ASME Code comply with the PED? Anchor Bolts and Base Rings Top How does COMPRESS treat anchor bolt design? How is the anchor bolt clearance defined? What is the procedure for performing the base ring anchor bolt calculation? Does COMPRESS check the minimum spacing of anchor bolts for skirt supported vessels? The COMPRESS database does not contain the bolt size I need for my flange (or for skirt base ring, etc). How do I add bolts to the database? Why doesn't COMPRESS apply the maximum bending moment to the anchor bolts in my base ring report? This results with the required area of the bolt being reported as zero (0)? COMPRESS uses only 60% of the weight for determining the tensile force in the anchor bolts when designing a vessel using the ASCE 7-05 Code. What is the reason for not using 100%? Does COMPRESS include an initial bolt preload when designing anchor bolts and base plate? What is the preload used? I receive a tailing lug deficiency message that states "The local stresses for the lug have not been calculated." What does this mean and why is it presented? Does COMPRESS apply the 1/3 increase in allowable stress permitted for structural steel by the AISC (American Institute of Steel Construction) Steel Design Standard? Appendix 2 Flanges Top How does COMPRESS determine the UG-99 stress ratio for flanges designed to Appendix 2? I get a value different from what is reported in the Hydrotest Report. Why aren't stresses determined for Appendix 2 flanges during the hydrostatic test? Instead, COMPRESS reports that the stress was not investigated ("NI")? How does COMPRESS consider external loads applied to body flanges? How do I design a flange with an O-ring gasket in COMPRESS? For design of Appendix 2 flanges, Table 2-5.2 provides two columns with formulas to be used for determining the basic gasket width 'bo'. How is the column selected in COMPRESS? ASME B16.5 and B16.47 Flanges Top How does COMPRESS determine hydrostatic test pressure? Is the effect of the test static head on components such as ANSI flanges considered? How are the hydrotest rules of UG-99 applied to ANSI/ASME flanges? Why can't I add user defined materials for use in specifying ANSI/ASME flanges? Why do I get the message "For Class 150 flanges, ASME B16.5 para. 5.4.3 recommends gaskets to be in accordance with Annex C, Table C1, Group No. I"? What does this message mean? ? May different materials be specified for a flange and its attached blind flange? Why do I receive the flange notification "NOTE: Suitable low temperature bolting material is required?" What does it mean? How are external loads acting on a standard body flange considered in COMPRESS? Hydrostatic test pressures for ASME B16.5 flanges attached to nozzles are listed in the COMPRESS nozzle report. How are the hydro test pressures for ASME B16.5 flanges determined? How do I specify a long weld neck flange to be used as a nozzle in COMPRESS? I want to attach a standard ASME B16.5/B16.47 blind flange to a studding outlet (COMPRESS Type 11 or Type 12 nozzle) but the button to attach flanges to the nozzle is disabled. Why? COMPRESS does not have a corrosion allowance input for ASME B16.5/B16.47 flanges. Why? How does COMPRESS determine the MDMT Rating and coincident ratio per UCS-66 for ASME B16.5 and B16.47 flanges? How does COMPRESS determine the MDMT for the flange portion of a Long Weld Neck (LWN)? Why doesn't COMPRESS rate the LWN flange to −20° F using UCS-66(c)? COMPRESS does not provide an option to select slip-on flanges greater than 24". How should these be specified? ASME Code Addenda Top COMPRESS will not let me update\change the ASME Addenda in a CW6 file (the Addenda selection is not available). Why? How can I update the Addenda selection? Some of our projects require the use of older (non-current) Code Addenda. Do I need to install a different COMPRESS version for each ASME Code Edition or Addenda that I want to use? Has COMPRESS undergone a certification process to verify the accuracy of the ASME Code calculations performed? Is COMPRESS verification documentation available? Bolted Covers Top Why does COMPRESS apply different values for "C" for internal and external pressure cases when designing a bolted cover per UG-34? Building Codes Top COMPRESS divides the calculated seismic base shear by 1.4. Where is this specified in Uniform Building Code (UBC)? What is the background of the Building Codes such as ASCE, BOCA and IBC? How do they fit into pressure vessel design? How does COMPRESS determine the wind force coefficient factors Cf applied to horizontal vessels? What specific conditions apply to the vessel "Empty" case? Does COMPRESS automatically increase the effective vessel OD to account for insulation? Does COMPRESS apply the 1/3 increase in allowable stress permitted for structural steel by the AISC (American Institute of Steel Construction) Steel Design Standard? Why does COMPRESS apply a factor 0.6 to the weight W when calculating anchor bolt loads and required thicknesses of shells based on longitudinal stress? Does COMPRESS consider vortex shedding? How do I turn vortex shedding on in COMPRESS? How do I change the UG-22 loadings specified in the Settings Summary? How does COMPRESS apply the rules of UBC for seismic design? Codeware Key Update Utility Top COMPRESS Key Update Procedure COMPRESS Key Update Procedure Frequently Asked Questions Cones (Transitions) Top I designed a cone but it is not oriented the right way. How do I correct this? How do I design an eccentric cone on a vertical vessel? How does COMPRESS calculate the minimum flare thickness for the case of internal pressure in transitions with flares. How does COMPRESS determine the maximum elongation for cones (transitions)? What does the message "Transition calculations cannot be completed until a cylinder is attached to the small [or large] end of the cone (or the discontinuity is eliminated)" mean? Cylinders Top Why does COMPRESS sometime increases the nominal thickness of cylinder components more than 1/16" (or 1/8") beyond the design thickness shown in the thickness summary table? Deficiencies and Warnings Top I receive deficiency "Do/t > 1000 which is outside of ASME code range. U-2(g) analysis performed. (warning)." This occurs for nozzles or cylindrical shell sections, but what does it mean? I get a deficiency for the cone report "Appendix 1-8(c): a stiffener ring is required at the cone small end" even though I have specified a stiffening ring for that juncture. Why? Why do I get the message "The length of the nozzle has been increased to satisfy the minimum nozzle projection requirement as specified under Action/Set Mode/Nozzles 1 tab" and what does it mean? I get a warning that the aspect ratio of long chord to nozzle ID exceeds 2.0. What does this mean and what do I do? My cone angle is less than 30°. Why does COMPRESS return a Deficiency "Transition calculations cannot be completed until a cylinder is attached to the large [or small] end of the cone (or the discontinuity is eliminated)"? How do I restore the Warnings after they have been suppressed? There's a switch on the Deficiencies message dialog but that dialog isn't displayed if there are no Deficiencies. What does the deficiency "Reinforcement pads are not recommended for temperatures where time dependent material properties govern (creep regime)" mean? I get a Deficiency for my flange bolts (below). How do I resolve this? I receive a "Rigid insert assumption questionable" warning message for a nozzle WRC-107 calculation.  What does it mean? I receive the deficiency “WRC-107: Geometry beyond the limits of shallow shell theory (at pad edge) WRC-107: Geometry beyond the limits of shallow shell theory” I received the deficiency "It is recommended that the skirt thickness be at least D/400". What does this mean? COMPRESS reports a Deficiency that the fillet weld at a nozzle-to-shell weld is too small for the MAP condition per UW-16. Doesn't COMPRESS automatically design for this condition? COMPRESS returns a deficiency that states "Actual lug C1/C2 < 1/4, C1/C2 = 1/4 used as this is the minimum ratio covered by WRC 107." What does this message mean? I obtain a Warning message for an internal head "Reduction in joint efficiency used in circumferential stress calculation may be required per UW-12(d). If required, the user defined joint option should be used. (warning)." How do I resolve this? I obtain a Warning message that a flange limits the nozzle MAWP. What does this indicate? A cylindrical shell receives the deficiency "Trial length contradicts actual length". What does this mean and how is it resolved? A nozzle receives deficiency "Required thickness tr for the input nozzle pressure exceeds the component wall thickness". What does this mean and how is it to be resolved? Drafter Top How do I customize the Vessel Drafting Program? Which AUTO Lisp source code may be modified? How do I export a file from COMPRESS to Vessel Drafting Program (VDP)? How do I customize the default title blocks in VDP? Vessel Drafting Program (VDP) will not draw using SI units or will not retain "SI" units selected in Drafter Setup menu. When I run Vessel Drafting Program (VDP), the VDP menus are not available. How can I resolve this? The Vessel Drafting Program (VDP) is unable to recognize my installation of AutoCAD. How can I resolve this? Error Messages Top Why do I receive the error message, "ASP Status : LM old version was found (42)(2)" when I try to run the network version of COMPRESS? I am receiving a registry error "Registry editing has been disabled by your editor" when I run COMPRESS. What can I do to resolve this issue? On start up, COMPRESS displays a message stating "An error was raised while trying to open Asme.mdb..." as shown below. What can I do to resolve this problem? I get a "Server Busy" error message when I try to start COMPRESS. What can I do about it? When I install COMPRESS, I get an error message saying "Setup has detected that UnInstallShield is in use. Please close UnInstallShield and restart setup. Error 432." How do I resolve this error message? COMPRESS crashes and produces an error message when ASME Code calculations are run (crashes after pressing the function key F3). How can I correct this problem? I get a Microsoft .NET Framework error 1603 when I try to install COMPRESS. What does this mean and what can I do to correct the problem? What should be done if an error stating "Registration of ASME_Calcs.dll failed" is displayed when COMPRESS starts up? I receive an error message "Calculate() failed [Input string was not in a correct format]" when calculations are run by pressing F3. How do I correct this? A "Render Error" is produced when COMPRESS starts. The message may be "Cannot get a D3D device for rendering" or a similar message. COMPRESS displays a message that reads "The Microsoft Flex Grid control MSFLXGRD.OCX may not be properly registered". How do I correct this? I receive an error message when I start COMPRESS Build 6260. What should I do? Recibo un mensaje de error cuando inicio COMPRESS Build 6260. ¿Qué debo hacer? COMPRESS Build 6260을 시작할 때 오류 메시지가 표시됩니다. 어떻게 해야 합니까? When I start COMPRESS build 6260, I receive the message "Invalid XML scope." How do I resolve this issue? Cuando inicio COMPRESS build 6260, recibo el mensaje "Alcance XML inválido". ¿Cómo soluciono el problema? COMPRESS build 6260을 실행하면 "Invalid XML scope"라는 메시지가 표시됩니다. 어떻게 해결합니까? Why do I still get an "Expired SUS!" message after I have renewed my Support and Update Service (SUS)? External Loads Top What is the basis for the "External Pressure + Weight + External Loading Check" analysis performed in COMPRESS? How are external loads on nozzles treated in COMPRESS? How does COMPRESS determine allowable compressive stress used in evaluating stresses in the longitudinal direction? How does COMPRESS consider external loads applied to body flanges? How do I determine the maximum external loads that can be applied to a nozzle? How are external loads acting on a standard body flange considered in COMPRESS? I get the warning "External loads may cause the pad to fail by buckling unless intermediate pad welds are used - See Bednar 7.5 paragraph 3." What does this mean and why do I get it? Numerical values for external nozzle loads in the WRC-107 report, such as ML and Mc, do not agree with the loads reported by the finite element analysis (FEA nozzles). Why? Why does COMPRESS not provide an option to attach "Clips/Lugs" (from Attach menu) to formed heads? Why does COMPRESS apply a factor 0.6 to the weight W when calculating anchor bolt loads and required thicknesses of shells based on longitudinal stress? Does COMPRESS consider vortex shedding? How do I turn vortex shedding on in COMPRESS? Does COMPRESS consider the required thickness for longitudinal stress? What loads and vessel conditions are considered? How do I turn on consideration of tower/column deflections due to wind in COMPRESS? How is the force due to vertical seismic acceleration determined for horizontal vessels? How are vertical and horizontal loads accounted for when considering base shear in the wind and seismic code reports? When external loads acting on the nozzle are specified in the WRC-107 function, COMPRESS also calculates the stress in the nozzle neck due to combined effect of internal pressure, axial load on nozzle, and net bending moment on nozzle. The allowable stress for this condition is determined from ASME Code Section VIII Division 2, Appendix 4-138(b). But COMPRESS limits the allowable stress to "S" (the basic allowable tensile stress) and does not account for local membrane stress PL. Why is PL not considered? External Pressure Top I receive deficiency "Do/t > 1000 which is outside of ASME code range. U-2(g) analysis performed. (warning)." This occurs for nozzles or cylindrical shell sections, but what does it mean? What is the basis for the "External Pressure + Weight + External Loading Check" analysis performed in COMPRESS? Why does COMPRESS use vacuum chart CS-3 for material SA-537? Shouldn't this be CS-4, since CS-4 applies to SA-537 material? How does COMPRESS determine the pressure due to operating liquid level? What density of water does COMPRESS use? How does COMPRESS determine the maximum allowable external pressure (MAEP) for transitions? Should the design pressure be entered as "gage" or "absolute" (eg. psig or psia, etc)? Finite Element Analysis (FEA) Top How do I update my COMPRESS license to include finite element analysis of nozzles (FEA-Nozzles) capabilities? Numerical values for external nozzle loads in the WRC-107 report, such as ML and Mc, do not agree with the loads reported by the finite element analysis (FEA nozzles). Why? How do I perform FEA on Nozzles? How do I specify that a nozzle fatigue analysis is to be performed? What is the difference between the FEA Nozzles option included in COMPRESS and the NozzlePRO software package? Flanges Top How are ANSI/ASME flanges treated in COMPRESS? How are the hydrotest rules of UG-99 applied to ANSI/ASME flanges? Why do ANSI/ASME flange materials not use the correct material designation? Why can't I add user defined materials for use in specifying ANSI/ASME flanges? Does COMPRESS distinguish between Series A and Series B ANSI flanges? How do I specify the series? Why do I get the message "For Class 150 flanges, ASME B16.5 para. 5.4.3 recommends gaskets to be in accordance with Annex C, Table C1, Group No. I"? What does this message mean? How does COMPRESS determine the bore dimension for Heavy Barrel flanges? How does COMPRESS determine the UG-99 stress ratio for flanges designed to Appendix 2? I get a value different from what is reported in the Hydrotest Report. How do I attach nozzles to standard blind flanges? How are long weld neck flange dimensions determined? Why does COMPRESS (or Modeler) not provide a selection for flange facing of standard ASME/ANSI B16.5/B16.47 flanges? How are raised face and ring type flanges to be distinguished? May different materials be specified for a flange and its attached blind flange? When designing a flange per Section VIII Division 1, Appendix 2 COMPRESS will increase the pressure if external moment and axial load exist on the flange. The equivalent pressure due to the moment and axial load is found. But this equivalent pressure is applied only to the term 'H' and not to 'HP' or 'HD'. Why isn't the equivalent pressure applied to these terms also? Why aren't stresses determined for Appendix 2 flanges during the hydrostatic test? Instead, COMPRESS reports that the stress was not investigated ("NI")? Why does COMPRESS report "N/A" (for "not available") on the Pressure Summary for MAEP of ASME B16.5 and B16.47 standard flanges and blind flanges? COMPRESS uses the combined thickness of the shell and flange hub as dimension "g0" when calculating slip-on integral flanges per Appendix 2. Shouldn't g0 be the thickness of the shell only? For Appendix 2 flanges COMPRESS reports only calculations based on the flange thickness entered. How does COMPRESS determine the required thickness reported for an Appendix 2 flange? How is the MAWP of the flange determined? How does COMPRESS consider external loads applied to body flanges? The MDMT rating of my ASME B16.5 or B16.47 flange is not what I was expecting. What could be the cause? How does COMPRESS design flanges with full face gaskets? What Edition of ASME B16.5 and ASME B16.47 does COMPRESS use for standard flanges? How do I specify a long weld neck flange to be used as a nozzle in COMPRESS? How do I design a flange with an O-ring gasket in COMPRESS? How do I specify that a nozzle is located in a blind flange? I obtain a Warning message that a flange limits the nozzle MAWP. What does this indicate? Forms Top How do I submit an ASME Form produced by COMPRESS to the National Board electronically? Heads Top Some unexpected results occur when designing heads: COMPRESS uses K factors different from what user expects and COMPRESS may return unusual values for thickness for high pressures. How does COMPRESS account for forming allowance on heads? What is the convention used in COMPRESS for defining angular orientation on heads? I designed a cone but it is not oriented the right way. How do I correct this? How do I design an eccentric cone on a vertical vessel? Does COMPRESS consider buckling in the head? Why does COMPRESS increase the minimum thickness that I enter for an F&D (or ellipsoidal) head? Why does COMPRESS apply joint efficiency E = 0.85 or E=0.70 when I specify a seamless hemispherical head? Shouldn't E = 1.0 for a seamless head? How can I specify an internal head in COMPRESS? The allowable stress used by COMPRESS in the design of a torispherical (F&D) head is lower than the value listed in ASME II-D. What is causing this? How do I specify the radiography to be performed at the circumferential seam of bottom head? COMPRESS has disabled the RT selection list. Why does COMPRESS occasionally increase the nominal thickness of a torispherical head beyond the required thickness shown (in grey next to the thickness input) in design dialog? How does COMPRESS determine the forming strain for ellipsoidal heads? How does COMPRESS determine the effective depth of the head, h, for external pressure? Why doesn't COMPRESS use the UG-32(d) formula for the design of a semi ellipsoidal head? Can this be changed? I obtain a Warning message for an internal head "Reduction in joint efficiency used in circumferential stress calculation may be required per UW-12(d). If required, the user defined joint option should be used. (warning)." How do I resolve this? Heat Exchangers Top How do I specify a jacketed vessel? Why do parts of the Vessel and Heat Exchanger Wizard dialogs get cut off on my screen? How do I specify that a heat exchanger is to be designed for external pressure? The heat exchanger data input screens don't allow me to enter all of my design temperature or corrosion details. How can I input the required temperature, MDMT or corrosion information into COMPRESS? How is the maximum stress range calculated for an expansion joint per TEMA RCB-8.83? And shouldn't Scl be within 1.5*S where S is the maximum allowable stress value? How does COMPRESS consider gasket grooves in tubesheets? Do I need to increase the thickness of a tubesheet calculated by COMPRESS to account for gasket grooves? COMPRESS does not perform tube-to-tube sheet joint calculations for U-tube heat exchangers. What is the reason for this? Why is the tubesheet thickness required by ASME UHX different\greater than the required thickness calculated by TEMA? How can I get thinner tubesheets when using ASME UHX? How do I add a tailing lug to a skirt supported (vertical) heat exchanger? How is the Allowable Stress for Tubesheet during hydrostatic test determined? When designing a tubesheet in accordance with ASME Part UHX, why does COMPRESS report an overstress of the tubesheet or shell (channel) during pressure test? Hydrotest Top How does COMPRESS determine the allowable stresses specified for hydrostatic testing; why does COMPRESS report different allowable stresses for the same material when used as a shell component or a nozzle? How does COMPRESS determine hydrostatic test pressure? Is the effect of the test static head on components such as ANSI flanges considered? How are the hydrotest rules of UG-99 applied to ANSI/ASME flanges? What is the option "calculate hydrotest stress"? How does COMPRESS determine the UG-99 stress ratio for flanges designed to Appendix 2? I get a value different from what is reported in the Hydrotest Report. Why aren't stresses determined for Appendix 2 flanges during the hydrostatic test? Instead, COMPRESS reports that the stress was not investigated ("NI")? Can COMPRESS consider wind loads during hydrotest? Where in the report are the resulting calculations located? Can COMPRESS perform hydrotest calculations in the corroded condition? What effect does butt weld joint efficiency have on the stress at hydrostatic test condition? How is the Allowable Stress for Tubesheet during hydrostatic test determined? What effect does butt weld joint efficiency have on the stress at hydrostatic test condition? When designing a tubesheet in accordance with ASME Part UHX, why does COMPRESS report an overstress of the tubesheet or shell (channel) during pressure test? Impact Testing Top When does COMPRESS apply the impact test exemption requirements of UCS-66? How does COMPRESS determine an exemption from impact testing requirements? How does COMPRESS determine the rated MDMT? Internal Pressure Top How does COMPRESS determine the pressure due to operating liquid level? What density of water does COMPRESS use? Why does COMPRESS apply different values for "C" for internal and external pressure cases when designing a bolted cover per UG-34? How does COMPRESS calculate the minimum flare thickness for the case of internal pressure in transitions with flares. How does COMPRESS handle static liquid pressure? Should the design pressure be entered as "gage" or "absolute" (eg. psig or psia, etc)? What is the "hot shut down" condition? Joint Efficiency Top How does COMPRESS determine the joint efficiency and exemption from impact testing requirements for welded and seamless pipes? How do I change the joint efficiency in the COMPRESS calculations? When designing the skirt, why does COMPRESS use joint efficiency = 1.0 instead of the values I have entered? Why does COMPRESS apply joint efficiency E = 0.85 or E=0.70 when I specify a seamless hemispherical head? Shouldn't E = 1.0 for a seamless head? What values should I enter for a skirt joint efficiency? Why does the joint efficiency (E) shown under the Nozzle Required Thickness Per UG-27(c)(1) not match the joint efficiency (E) reported under the UG-45 Nozzle Neck Thickness Check? How does COMPRESS consider the joint efficiency of a nozzle neck fabricated from rolled plate? What effect does butt weld joint efficiency have on the stress at hydrostatic test condition? Where can I find more information on the ASME Code's joint efficiency rules? How does COMPRESS determine joint efficiency? Legs Top How does COMPRESS determine what allowable stress factor increase to use? How does COMPRESS treat anchor bolt design? How does COMPRESS determine the values of C1 and C2 when calculating stresses at the shell to leg attachment location? Is there a stiffening effect due to the head? Why won't COMPRESS allow me to attach clips/lugs or legs to heads? Why is the saddle support listed in the Pressure Summary and how may it limit my vessel MAWP? In some cases COMPRESS increases the height I have specified for the reinforcing pad of support legs. What rules does COMPRESS follow to determine the height and location of reinforcing pads for legs? Does COMPRESS apply the 1/3 increase in allowable stress permitted for structural steel by the AISC (American Institute of Steel Construction) Steel Design Standard? What is the basis of the COMPRESS support leg analysis? How do I add a new pipe size to the support leg table? How can I attach support legs to the bottom head? Lifting Lugs, Clips and Stiffener Beams Top How does COMPRESS determine what allowable stress factor increase to use? How does COMPRESS determine the allowable stresses for lifting lugs? Why isn't the option to allow "Use MAWP" available on the leg design dialog (or support lug, or support saddle dialog)? COMPRESS refers to a stiffener beam in the tailing lug calculation. What is a “stiffener beam” and what is its purpose? Why does COMPRESS not provide an option to attach "Clips/Lugs" (from Attach menu) to formed heads? I receive a tailing lug deficiency message that states "The local stresses for the lug have not been calculated. "What does this mean and why is it presented? How do I add a tailing lug to a skirt supported (vertical) heat exchanger? COMPRESS returns a deficiency that states "Actual lug C1/C2 < 1/4, C1/C2 = 1/4 used as this is the minimum ratio covered by WRC 107." What does this message mean? Materials Top How do I add a material to the material database? How do I specify materials that are not defined in ASME Section II Part D? Why can't I add user defined materials for use in specifying ANSI/ASME flanges? Where can I find and how may I add more materials for use in specifying vessel components? May different materials be specified for a flange and its attached blind flange? Why does COMPRESS use vacuum chart CS-3 for material SA-537? Shouldn't this be CS-4, since CS-4 applies to SA-537 material? How can I use the same user-defined material at different temperature? What does the "Edit All Stress Values" button do on the user-defined material dialog? How do user defined materials in COMPRESS differ from materials found in the ASME materials database? COMPRESS occasionally reports the message "Material is not produced to Fine Grain Practice”. What is meant by the term "Fine Grain Practice"? How can I retain my existing user-defined materials and structures when I updating to a new COMPRESS build? How do I specify materials that are not defined in ASME Section II, Part D? Some materials listed in ASME Section II Part D have different allowable stresses at the same design temperature. How do I know which set of allowable stresses to use? Does COMPRESS provide these? MAWP/MAP Top Why does COMPRESS use the saddle web thickness in the Ring Compression Stress calculation? It should use the saddle width? How does COMPRESS determine the MAWP and MAP for transitions? How does COMPRESS determine the MAWP and MAP for nozzles? Some nozzles may be exempted by UG-36(c)(3)(a) from area replacement requirements. How does COMPRESS determine the MAWP and MAP for these nozzles? Why isn't the option to allow "Use MAWP" available on the leg design dialog (or support lug, or support saddle dialog)? Why is the saddle support listed in the Pressure Summary and how may it limit my vessel MAWP? How do we specify a mode to calculate the MAWP and MAP which shall be limited by shell, heads or flange rating only (not the nozzle neck)? For Appendix 2 flanges COMPRESS reports only calculations based on the flange thickness entered. How does COMPRESS determine the required thickness reported for an Appendix 2 flange? How is the MAWP of the flange determined? How does COMPRESS calculate the MAP of transitions? Does the orientation of the vessel affect this calculation? Why aren't the MAWP and MAP of a transition (cone) identical when the allowable stresses are equal for the two temperature conditions? How do I determine what component limits the vessel's MAWP? How do I design a vessel whose MAWP is not limited by the nozzles? MDMT Top When determining the MDMT rating per Figure UCS-66.2 COMPRESS bases the coincident ratio on longitudinal stress (as reported in the output) for seamless cylinders but not for welded cylinders. Why? How does COMPRESS determine an exemption from impact testing requirements? How does COMPRESS determine the rated MDMT? The MDMT rating of my ASME B16.5 or B16.47 flange is not what I was expecting. What could be the cause? How does COMPRESS determine the MDMT Rating and coincident ratio per UCS-66 for ASME B16.5 and B16.47 flanges? How does COMPRESS determine the MDMT rating for ANSI/ASME standard carbon steel flanges? How does COMPRESS determine the MDMT rating for nozzle reinforcing pads? How does COMPRESS determine the MDMT for the flange portion of a Long Weld Neck (LWN)? Why doesn't COMPRESS rate the LWN flange to −20° F using UCS-66(c)? COMPRESS determines the "lowest MDMT without impact testing" using the procedure in Figure UCS-66.1. Can this temperature reduction be disabled so that the MDMT rating is based only on Figure UCS-66? Networking Top Why am I sometimes unable to save COMPRESS files on a network drive? How do I install the network version of COMPRESS? How can system administrators and others prevent COMPRESS build 6221 and later from automatically checking for software updates through the internet when the program is started? The starting time for COMPRESS is unusually long. How can I shorten the start up time? Can I run COMPRESS if I don't have administrative rights to my computer? Is COMPRESS compatible with Microsoft Windows Vista? Is COMPRESS compatible with 64-bit versions of Microsoft Windows? How do I transfer the COMPRESS network installation to another key server computer? I get a "COMPRESS update failed" message when I try to use the COMPRESS online update. Why won't the update work? The COMPRESS component reports are printed in a different order than was selected. What is causing this? How do I verify that my key server computer has HASP drivers, HASP License Manager and Codeware Key Manager installed? What is HASP License Manager and how does it work with COMPRESS? I have both single user and network COMPRESS licenses (keys). How can I switch between my single user and network licenses (keys)? The network license does not release when a user closes COMPRESS which prevents other users from accessing the license. How do I correct this issue? I receive an error message when I start COMPRESS Build 6260. What should I do? Recibo un mensaje de error cuando inicio COMPRESS Build 6260. ¿Qué debo hacer? COMPRESS Build 6260을 시작할 때 오류 메시지가 표시됩니다. 어떻게 해야 합니까? How can I access COMPRESS on a client PC when the Key Server is on a different subnet (e.g. VPN)? ¿Cómo puedo acceder a COMPRESS en una PC cliente cuando el servidor de claves está en una subred diferente (por ej. VPN)? 키 서버가 다른 서브넷(예: VPN)에 있을 때 클라이언트 PC에서 COMPRESS를 어떻게 액세스합니까? Nozzles Top Why does COMPRESS not use the design pressure when reporting the nozzle calculations (nozzle report)? What pressure is used for designing nozzles? How does COMPRESS determine the MAWP and MAP for nozzles? Some nozzles may be exempted by UG-36(c)(3)(a) from area replacement requirements. How does COMPRESS determine the MAWP and MAP for these nozzles? How does COMPRESS determine which nozzles fall under the category of "large openings" subject to the rules of Appendix 1-7? How are external loads on nozzles treated in COMPRESS? I have specified a nozzle neck made of welded pipe. Why does COMPRESS divide allowable stress by 0.85 when calculating nozzle required thickness 'trn'? How do I attach nozzles to standard blind flanges? What happens when a nozzle's reinforcement extends beyond the nozzle's parent component and onto adjacent components? How does COMPRESS handle this situation and what are the implications? How is the nozzle projection from outside surface, Lpr, defined? Why doesn't the required thickness 'tn' in the Nozzle Summary match that shown in the nozzle report? Why doesn't COMPRESS provide calculations for required fillet weld on internal projection of some nozzles? Why does COMPRESS apply numerical factor "2" when considering the nozzle reinforcing area A2? This should be "5" as per Figure UG-37.1? Why doesn't COMPRESS determine the alternate minimum required thickness of ellipsoidal heads as per UG-32(b)? COMPRESS reports that a small diameter nozzle has inadequate reinforcing area for design pressure (or reports nozzle MAWP < Design Pressure). But shouldn't the nozzle should be exempted by size based on UG-36(c)(3)(a)? How does COMPRESS apply the minimum nozzle projection from Set Mode Options when there is a flange or when the nozzle is an integral forging with flange? How do I design offset or tilted nozzles on sump? The only option available is for "radial" nozzles. How do I determine the maximum external loads that can be applied to a nozzle? How do I locate a nozzle in a head? Can COMPRESS model a localized thickness increase? Due to an external loading on a nozzle I need a large reinforcement pad. I receive a warning that the pad is outside the limits of reinforcement. Is there a way to model an internal plate that will allow for this? Does COMPRESS calculate elliptical (obround) openings? Why does the joint efficiency (E) shown under the Nozzle Required Thickness Per UG-27(c)(1) not match the joint efficiency (E) reported under the UG-45 Nozzle Neck Thickness Check? How does COMPRESS consider the joint efficiency of a nozzle neck fabricated from rolled plate? How do I update my COMPRESS license to include finite element analysis of nozzles (FEA-Nozzles) capabilities? Why are the reinforcing areas shown in the nozzle reports different from those shown in the status bar at the bottom of the nozzle design dialog? How do I specify a long weld neck flange to be used as a nozzle in COMPRESS? How does COMPRESS account for internal projection of nozzles? Where is the internal projection measured from? Does COMPRESS account for the 'drop' or versine of nozzles with square-cut ends? How does COMPRESS determine the chord opening for offset nozzles in cylinders? How does COMPRESS determine the MDMT for the flange portion of a Long Weld Neck (LWN)? Why doesn't COMPRESS rate the LWN flange to −20° F using UCS-66(c)? What is ASME Appendix 1-10? Why does COMPRESS apply Division 2 rules for nozzle design to my Division 1 vessel? How do I specify that a nozzle is located in a blind flange? I receive a Warning message "Overlapping limits of reinforcement between nozzles N1 and N2 detected - user intervention may be required" when calculations are run. What action is necessary? How does COMPRESS determine the "reinforcing pad diameter" for offset nozzles? Is the width of the reinforcing pad required to be maintained around the entire nozzle circumference or may a circular pad be used? COMPRESS reports a Deficiency that the fillet weld at a nozzle-to-shell weld is too small for the MAP condition per UW-16. Doesn't COMPRESS automatically design for this condition? COMPRESS reports this formula, tr = P*Ro/(2SE+0.8P), for "tr" in the UG-37 calculation. This formula is not in the ASME Code book; how is it developed? Pipe, Couplings and Pipe Caps Top How do I add elbows, tees or other piping components to COMPRESS? I have specified a nozzle neck made of welded pipe. Why does COMPRESS divide allowable stress by 0.85 when calculating nozzle required thickness 'trn'? Why doesn't the required thickness 'tn' in the Nozzle Summary match that shown in the nozzle report? Why does COMPRESS sometimes apply a factor of (1/0.85) when calculating required cylinder thicknesses due to external loads? Why doesn't COMPRESS subtract the pipe mill tolerance in the shell thickness "t" when performing the nozzle reinforcing calculations per UG-37? Program Operations Top Questions regarding level of detail of screen graphics Why do parts of the Vessel and Heat Exchanger Wizard dialogs get cut off on my screen? What do the locked fields "Top Head Start" and "Top Head End" on the platform design dialog indicate? How do I create a template file for Vessel Wizard? I am trying to add a component to the top of my vessel, but the component is added to the bottom. How can I add my component to a location other than the bottom? How do I change the orientation of my vessel from vertical to horizontal and vice versa? How can I add a custom user-defined structure (vacuum ring, support leg, stiffener ring, etc.) to COMPRESS? COMPRESS saves files with several different extensions. Please explain what the extensions are associated with. How do I change the default color scheme used by COMPRESS? COMPRESS will not let me update\change the ASME Addenda in a CW6 file (the Addenda selection is not available). Why? How can I update the Addenda selection? How do I submit an ASME Form produced by COMPRESS to the National Board electronically? How is the datum referenced? Ladders: drawing and orientation Program Troubleshooting Top Does COMPRESS provide an "auto save" or file backup feature? How can I save PDF reports if I don't have administrative rights to my computer? How do I make a screen print of a message or dialog? How can I get COMPRESS to automatically detect when a new software update is available? I am running into complications when running COMPRESS with my Anti-Virus software. How can I resolve this? If I update to a newer version of COMPRESS, will my settings be preserved? How do I ensure I am running the latest version of FEA-Nozzles? Can I run COMPRESS if I don't have administrative rights to my computer? What are the system requirements to run COMPRESS? Is COMPRESS compatible with Microsoft Windows Vista? Is COMPRESS compatible with 64-bit versions of Microsoft Windows? COMPRESS saves files with several different extensions. Please explain what the extensions are associated with. I cannot find the COMPRESS "cw6" file in Windows Explorer; only "cw5" files are listed. What is Data Execution Prevention (DEP) and how can I run it with COMPRESS if it is enabled on my system? Should I insure my Codeware software license(s) against loss or theft? What is the replacement cost in the event my license (hardware key) is lost or stolen? I get a "COMPRESS update failed" message when I try to use the COMPRESS online update. Why won't the update work? COMPRESS will not let me update\change the ASME Addenda in a CW6 file (the Addenda selection is not available). Why? How can I update the Addenda selection? The COMPRESS component reports are printed in a different order than was selected. What is causing this? How do I submit an ASME Form produced by COMPRESS to the National Board electronically? How do I open a port in Windows Firewall for Windows XP? Radiography Top I have a vessel design that requires an "RT2" designation. I selected 100% (full) RT on the longitudinal seams and Spot RT on the circumferential (girth) seams but the COMPRESS summary reports "RT3" in the summary report. How do I get COMPRESS to report "RT2"? How does COMPRESS consider the joint efficiency of a nozzle neck fabricated from rolled plate? What effect does butt weld joint efficiency have on the stress at hydrostatic test condition? How do I specify the radiography to be performed at the circumferential seam of bottom head? COMPRESS has disabled the RT selection list. What effect does butt weld joint efficiency have on the stress at hydrostatic test condition? Reports Top Why don't the loads and moments entered into the FEA-Nozzle inputs match those shown in the output report? How do I change the font size for headers and footers in the COMPRESS report? Why doesn't the required thickness 'tn' in the Nozzle Summary match that shown in the nozzle report? Why is the saddle support listed in the Pressure Summary and how may it limit my vessel MAWP? Under column 'Shell Design Thickness' why doesn't the required thickness 'tr' in the Nozzle Summary match that shown in the cylinder (head, etc) report? Why don't the bending moments reported in the Legs report match those in the Wind or Seismic reports? Why does COMPRESS report "N/A" (for "not available") on the Pressure Summary for MAEP of ASME B16.5 and B16.47 standard flanges and blind flanges? COMPRESS reports that a small diameter nozzle has inadequate reinforcing area for design pressure (or reports nozzle MAWP < Design Pressure). But shouldn't the nozzle should be exempted by size based on UG-36(c)(3)(a)? What specific conditions apply to the vessel "Empty" case? How can I modify the text in the "Additional Text" section in the Cover Page of the reports? How can I save PDF reports if I don't have administrative rights to my computer? I cannot create COMPRESS reports in PDF and have Full Control access to the COMPRESS folder. How do I resolve this issue? How are the allowable stresses in the skirt reports determined? The COMPRESS report doesn't contain enough detail to verify the calculations performed. How can I validate output from COMPRESS? How do I customize my PDF reports? What are the "Bending + axial stress in the saddle due to end loads" calculations used for? What is the vessel height "h" reported in the Wind Code report? Is wind applied below vessel support lugs or skirt? How do I print the report with consecutive page numbering? How can I include the Table of Contents in the PDF report? Can COMPRESS consider wind loads during hydrotest? Where in the report are the resulting calculations located? Why is the Cover Page not included when I generate my PDF report? How do I specify that the vessel picture ("snapshot") should be placed on the Cover Page? If the vessel snapshot does not appear on the Cover Page, how do I fix this? What is included in the lift weight reported by COMPRESS? The left-side print margins in COMPRESS build 6253 are too small. How can I print reports with the correct formatting? I see there is a consideration for lethal service in the COMPRESS Design Settings Summary. Where is lethal service specified in COMPRESS? Why are the reinforcing areas shown in the nozzle reports different from those shown in the status bar at the bottom of the nozzle design dialog? The COMPRESS component reports are printed in a different order than was selected. What is causing this? How do I change the UG-22 loadings specified in the Settings Summary? How do I submit an ASME Form produced by COMPRESS to the National Board electronically? "External pressure governs the test pressure per UG-99(f)" is reported in the hydrostatic test report. What does this mean? How can I shorten my COMPRESS reports? I receive an error message "Calculate() failed [Input string was not in a correct format]" when calculations are run by pressing F3. How do I correct this? How are vertical and horizontal loads accounted for when considering base shear in the wind and seismic code reports? I am obtaining "blank" nozzle reports. There is a title caption but the body of the report is blank. Why? Can COMPRESS produce calculation reports in both Metric and US Customary units? Rings Top What is the meaning of the "Max. Depth to Thickness Ratio" input for vacuum rings? What is the procedure for performing the base ring anchor bolt calculation? Why doesn't COMPRESS apply the maximum bending moment to the anchor bolts in my base ring report? This results with the required area of the bolt being reported as zero (0)? What shell thickness does COMPRESS apply when determining the MAEP (maximum allowable external pressure) of the vacuum rings? What location on the ring does COMPRESS use when locating vacuum rings from the datum? Do vacuum rings locations refer to the bottom of the ring, middle or top of the ring? How does COMPRESS size ring girders? Saddles Top Why does COMPRESS use the saddle web thickness in the Ring Compression Stress calculation? It should use the saddle width? Why is the saddle support listed in the Pressure Summary and how may it limit my vessel MAWP? Why does COMPRESS not include the weight of the saddles when determining (1) the base shear due to earthquake and (2) the "Q" loads in the Zick analysis? What is the factor "G" applied in the wind calculations for horizontal vessels? (applied in Saddle report under captions "Transverse wind shear on vessel" and "End wind shear on vessel")? How do I specify corrosion allowance for saddle stiffener rings that are inside the vessel? Can I add more than 2 saddles to a horizontal vessel in COMPRESS? What are the "Bending + axial stress in the saddle due to end loads" calculations used for? COMPRESS provides base shear and bending moment summaries for "vertical" vessels supported by skirts and legs.  Why is a similar summary not provide for "horizontal" vessels supported by saddles? Security/Hard Lock Key Issues (HASP) Top COMPRESS Key Update Procedure COMPRESS Key Update Procedure Frequently Asked Questions Why do I receive the error message, "HASP Status : LM old version was found (42)(2)" when I try to run the network version of COMPRESS? How do I obtain and customize the Nethasp.ini file on the COMPRESS "client" computers to specify the network address of the Key Server? My HASP key is not communicating with my computer. How can I check to see if my key is defective? How do I determine which users are currently accessing our COMPRESS network licenses? How do I transfer the COMPRESS network installation to another key server computer? What procedure should I follow if I receive the message below indicating that HASP Status: Number of stations exceeded. (42)(0)? Should I insure my Codeware software license(s) against loss or theft? What is the replacement cost in the event my license (hardware key) is lost or stolen? How do I verify that my key server computer has HASP drivers, HASP License Manager and Codeware Key Manager installed? What is HASP License Manager and how does it work with COMPRESS? I have both single user and network COMPRESS licenses (keys). How can I switch between my single user and network licenses (keys)? I am having trouble using the supplied .cw6p password file. After double clicking the .cw6p password file, Key Manager crashes and displays an error message. How do I resolve this and finish updating my key? After double clicking on the .cw6p password file, I get a "Windows cannot open this file:" error message. How do I resolve this and finish updating my key? The network license does not release when a user closes COMPRESS which prevents other users from accessing the license. How do I correct this issue? I receive an error message when I start COMPRESS Build 6260. What should I do? Recibo un mensaje de error cuando inicio COMPRESS Build 6260. ¿Qué debo hacer? COMPRESS Build 6260을 시작할 때 오류 메시지가 표시됩니다. 어떻게 해야 합니까? How can I configure the HASP License Manager on a COMPRESS "client" computer to specify the Key Server's network address? Software Updates/Installation Top If I update to a newer version of COMPRESS, will my settings be preserved? Is COMPRESS compatible with Microsoft Windows Vista? Is COMPRESS compatible with 64-bit versions of Microsoft Windows? I get a Microsoft .NET Framework error 1603 when I try to install COMPRESS. What does this mean and what can I do to correct the problem? How can I retain my existing user-defined materials and structures when I updating to a new COMPRESS build? Has COMPRESS undergone a certification process to verify the accuracy of the ASME Code calculations performed? Is COMPRESS verification documentation available? How do I install COMPRESS Build 6260 (single user mode)? Support Skirts Top Does COMPRESS check the minimum spacing of anchor bolts for skirt supported vessels? COMPRESS will not allow me to attach a skirt to a transition (cone). Why? How do I specify that the support skirt base ring is welded, not bolted, to the (skid) base plate? How can I model a stainless steel vessel with a stainless steel support skirt that extends into a carbon steel support skirt? What is the difference between an Intermediate Skirt and a Support Skirt in COMPRESS? Thickness Calculations Top Why does COMPRESS change thicknesses, bolt sizes, etc. without any warning to the user? Why does COMPRESS sometime apply a factor of 1/0.85 when calculating required thickness values? Under column 'Shell Design Thickness' why doesn't the required thickness 'tr' in the Nozzle Summary match that shown in the cylinder (head, etc) report? How does COMPRESS determine the nominal thicknesses entered into the component design dialogs? Can I specify decimal thicknesses? Why doesn't COMPRESS determine the alternate minimum required thickness of ellipsoidal heads as per UG-32(b)? COMPRESS doesn't subtract the pipe mill tolerance in the shell thickness "t" when performing the nozzle reinforcing calculations per UG-37. Why? What shell thickness does COMPRESS apply when determining the MAEP (maximum allowable external pressure) of the vacuum rings? How does COMPRESS determine the maximum elongation for cones (transitions)? Why does COMPRESS occasionally increase the nominal thickness of a torispherical head beyond the required thickness shown (in grey next to the thickness input) in design dialog? Why does COMPRESS increase the nominal thickness of cylinder components more than 1/16" (or 1/8") beyond the design thickness shown in the Thickness Summary table? How does COMPRESS account for pipe mill tolerance when using the wall thickness? COMPRESS automatically increases cylinder and cone thicknesses based on external pressure as additional components are added and Le increases. The designer is forced to add vacuum rings or adjust thicknesses later. Is there an easier way? COMPRESS reports this formula, tr = P*Ro/(2SE+0.8P), for "tr" in the UG-37 calculation. This formula is not in the ASME Code book; how is it developed? Transitions Top How does COMPRESS determine the MAWP and MAP for transitions? How do I design an eccentric transition? There is no option on the Transition component dialog to specify that the transition is eccentric. COMPRESS will not allow me to attach a skirt to a transition (cone). Why? How does COMPRESS calculate the MAP of transitions? Does the orientation of the vessel affect this calculation? Why aren't the MAWP and MAP of a transition (cone) identical when the allowable stresses are equal for the two temperature conditions? Units of Measurement Top What units of measurement does COMPRESS use for pressure, stress, etc? The coordinate system shown does not seem to match the typical right hand global coordinate system. How does COMPRESS define its coordinate system and how does it compare with the coordinate systems for WRC-107 and for FEA. In US Customary units, how do I enter a value in feet for length dimensions in COMPRESS? What format should I follow to enter the value correctly? Vacuum Rings Top What is the meaning of the "Max. Depth to Thickness Ratio" input for vacuum rings? What shell thickness does COMPRESS apply when determining the MAEP (maximum allowable external pressure) of the vacuum rings? Verification Top Has COMPRESS undergone a certification process to verify the accuracy of the ASME Code calculations performed? Is COMPRESS verification documentation available? Welds Top Minimum fillet weld sizes at nozzles per UW-16 should be based on the nominal thickness of the material in the new condition. So why does COMPRESS determine the weld size based on the corroded thicknesses? How does COMPRESS determine the joint efficiency and exemption from impact testing requirements for welded and seamless pipes? How do I change the joint efficiency in the COMPRESS calculations? When designing the skirt, why does COMPRESS use joint efficiency = 1.0 instead of the values I have entered? Why doesn't COMPRESS provide calculations for required fillet weld on internal projection of some nozzles? Why does COMPRESS apply joint efficiency E = 0.85 or E=0.70 when I specify a seamless hemispherical head? Shouldn't E = 1.0 for a seamless head? Why does COMPRESS apply joint efficiency E = 0.85 when I specify a seamless semi-ellipsoidal or torispherical head? Shouldn't E = 1.0 for a seamless head? What values should I enter for a skirt joint efficiency? What does the COMPRESS message "The minimum length of required taper", that references Fig UW-13.1(l)->(o), mean? Why does COMPRESS require post weld heat treatment (PWHT) for P-No 1 materials between 1-1/4" and 1.5" thick which have been preheated to 200 degrees F? WRC-107 Calculations Top What pressure does COMPRESS apply when performing the WRC-107 calculations? How are external loads on nozzles treated in COMPRESS? How does COMPRESS determine the values of C1 and C2 when calculating stresses at the shell to leg attachment location? Is there a stiffening effect due to the head? Why is the WRC-107 analysis not available for nozzles attached to flat welded or flat bolted covers? Why does COMPRESS use WRC-107 as the default method of analysis for external nozzle loads? Shouldn't WRC-297 be used? The coordinate system shown does not seem to match the typical right hand global coordinate system. How does COMPRESS define its coordinate system and how does it compare with the coordinate systems for WRC-107 and for FEA. How do I determine the maximum external loads that can be applied to a nozzle? I receive the deficiency “WRC-107: Geometry beyond the limits of shallow shell theory (at pad edge) WRC-107: Geometry beyond the limits of shallow shell theory” Why does COMPRESS use the curves for solid attachments when performing WRC-107 calculations for nozzles on heads?  What does the warning "Rigid insert assumption questionable" mean? Numerical values for external nozzle loads in the WRC-107 report, such as ML and Mc, do not agree with the loads reported by the finite element analysis (FEA nozzles). Why? Why does COMPRESS not provide an option to attach "Clips/Lugs" (from Attach menu) to formed heads? Why does COMPRESS use the "PVP-399" method to determine the pressure stress intensity factor "I" for the WRC 107 analysis? Can't the stress indices in ASME Section VIII Division 2, AD-56.7 be used instead? How does COMPRESS determine allowables for stresses determined by WRC-107? How does COMPRESS account for stresses due to pressure in the WRC-107 calculations for external loads? COMPRESS returns a deficiency that states "Actual lug C1/C2 < 1/4, C1/C2 = 1/4 used as this is the minimum ratio covered by WRC 107." What does this message mean? When external loads acting on the nozzle are specified in the WRC-107 function, COMPRESS also calculates the stress in the nozzle neck due to combined effect of internal pressure, axial load on nozzle, and net bending moment on nozzle. The allowable stress for this condition is determined from ASME Code Section VIII Division 2, Appendix 4-138(b). But COMPRESS limits the allowable stress to "S" (the basic allowable tensile stress) and does not account for local membrane stress PL. Why is PL not considered?